Side retainer plate for variable bore ram packer for a ram type blowout preventer

ABSTRACT

A variable bore ram packer including a ram body, a top seal and a packer member designed for use in a standard ram-type blowout preventer used in oil and gas drilling operations is disclosed. A side retainer plate is molded into the edges of the packer member. The side retainer plate includes a depending lip portion to minimize extrusion of the elastomeric material between the packer member and the guideways of the blowout preventer.

BACKGROUND OF THE INVENTION

[0001] 1. Field of the Invention

[0002] This invention relates to a side retainer plate for use invariable bore ram packers for a ram-type blowout preventer used in oiland gas drilling operations. The side retainer plate is intended tocontain rubber in the variable bore ram packers to prevent excessiverubber loss which can lead to premature wear. This allows the packer tooperate within the ram guideways of the blowout preventer for a longerperiod of time without damaging the ram guideway and preventspressurized well bore fluid leaking.

[0003] Ram-type blowout preventers are part of a pressure control systemused in oil and gas drilling operations to control unexpected well borepressure spikes or “kicks” as they are commonly referred to in theindustry. The blowout preventer has a body with a vertical bore and apair of laterally disposed opposing bonnet assemblies. Each bonnetassembly includes a piston which is laterally moveable within the bonnetassembly by pressurized hydraulic fluid. Replaceable sealing elementscalled “packers” are mounted within rams attached to the ends of thepistons which extend into the blowout preventer bore. When these pistonsare moved to a closed position, commonly referred to as “closing theblowout preventer” or “closing the rams”, the vertical bore of theblowout preventer is sealed and the kick is contained. These packers areavailable in a variety of configurations designed to seal the blowoutpreventer bore when the opposing rams and pistons are moved to theirclosed position.

[0004] One type of ram with packer has ends designed to seal around pipeof a specific size in the blowout preventer bore when the blowoutpreventer is closed. Other rams with packers are configured to sealaround a range of pipe sizes. It is the type designed to seal around arange of pipe sizes, called variable bore ram packers to which thepresent invention is directed. The ram packers form a pressure tightseal during a kick until the well bore pressure can be controlled. Thewell bore pressure can reach several thousand pounds per square inchduring a kick. Each ram packer has a semicircular opening in its frontface to form a seal around 1800 of the outer periphery of the pipe. Whenthe rams are closed as described above, the opposing ram packers meetand seal the entire 360° periphery of the pipe. The novel side retainerplate of the present invention is designed for use in a variable boreram packer and has a depending edge or lip to prevent excessive rubberloss of the side block seals of the ram packer which can lead topremature wear. This allows the packer to operate within the ramguideways of the blowout preventer for a longer period of time withoutdamaging the ram guideway and prevents pressurized well bore fluidleaking

[0005] 2. Description of Related Art

[0006] The use of metal inserts in a conical-type blowout preventer isdisclosed in U.S. Pat. No. 2,846,178 to B. S. Minor.

[0007] U.S. Pat. No. 3,897,038 to R. K. Le Rouax shows a ram typeblowout preventer using metal inserts as an anti-extrusion means.

[0008] The use of metal inserts in an annular blowout preventer tocontrol the stress level in the elastomeric packer unit is shown in U.S.Pat. No. 3,917,293 to G. E. Lewis et al.

[0009] U.S. Pat. No. 4,099,699 to H. Allen shows the use of irisingmetal inserts in an annular blowout preventer.

[0010] Another example of metal inserts in a variable bore blowoutpreventer in disclosed in U.S. Pat. No. 4,229,012 to B. C. Williams,III.

[0011] U.S. Pat. No. 4,444,404 to G. C. Parks, Jr. shows an example of avariable bore ram packer with interlocking anti-extrusion metal inserts.

[0012] Another example of a variable bore ram packer with interlockinganti-extrusion metal inserts is disclosed in U.S. Pat. No. 4,458,876 toG. R. Schaeper et al.

[0013] U.S. Pat. No. 4,550,895 to D. U. Shaffer shows an early versionof a variable bore ram packer. This apparatus utilizes a plurality ofannular segments embedded in the elastomeric rubber to aid ineffectuating a seal.

[0014] U.S. Pat. No. 6,367,804 B1 to G. D. Watts discloses variable boreram packer utilizing a pillar insert with top and bottom plates that arerotatable with respect to one another to allow sealing on taper tooljoint connections.

SUMMARY OF THE INVENTION

[0015] The side retainer plate of the present invention is designed foruse in a variable bore ram packer in a standard ram-type blowoutpreventer used in oil and gas drilling operations. The blowout preventerhas a body with an axial bore, a pair of opposing bonnet assemblies anda pair of opposing rams laterally moveable within the bonnet assembliesby a pressurized fluid source to control flow of well fluids through theblowout preventer body axial bore. The variable bore ram packer includesa ram body, a top seal and a packer member. The packer member is moldedof an elastomeric material having a central opening sized to fit closelyabout a tubular member when the blowout preventer is closed. The packermember includes a plurality of packer inserts molded within theelastomeric material surrounding the central opening of the elastomericmaterial. The packer member and the plurality of packer inserts aremolded into a unitary structure allowing the plurality of packer insertsto move and seat against different diameter tubular members to preventextrusion of the elastomeric material between the packer inserts and thetubular member.

[0016] The unitary structure includes a pair of side block seals moldedintegrally therewith. The side block seals have an upper and lower facewith a side retainer plate of the present invention within each of theupper and lower faces. The side retainer plate includes a planarportion, positioned parallel to the upper and lower faces, and adepending outer portion that is molded below the surface of the sideblock seals to conform to the ram guideway of the blowout preventer.

[0017] The packer inserts include a top plate, a bottom plate and acentral web positioned therebetween and integrally formed therewith. Thetop and bottom plates are a substantially triangular shape and each ofthe top and bottom plates includes a guide lip and a guide shoulder. Theguide lips and guide shoulders of adjacent top plates and the guide lipsand guide shoulders of adjacent bottom plates coact to provide anirising motion to the top and bottom plates as the top and bottom platesmove and seat against different diameter tubular members. Thesimultaneous movement of the top and bottom plates of the insert allowsthe top and bottom plates to move and seat against the tubular member.

[0018] A principal object of the present invention is to provide a sideretainer plate for use in a variable bore ram packer that minimizesrubber extrusion around the sides of the ram packer.

[0019] A further object of the present invention is to provide a sideretainer plate for use in a variable bore ram packer that can maintainthe rubber in the variable bore ram packer and minimize premature wear.

[0020] These with other objects and advantages of the present inventionare pointed out with specificness in the claims annexed hereto and forma part of this disclosure. A full and complete understanding of theinvention may be had by reference to the accompanying drawings anddescription of the preferred embodiments.

BRIEF DESCRIPTION OF THE DRAWINGS

[0021] These and other objects and advantages of the present inventionare set forth below and further made clear by reference to the drawings,wherein:

[0022]FIG. 1 is a perspective view illustrating a cutaway section of atypical ram-type blowout preventer used in oil and gas drillingoperations with the side retainer plate of the present invention in avariable bore ram packer shown installed within.

[0023]FIG. 2 is an exploded view of a variable bore ram packer with theside retainer plates of the present invention.

[0024]FIG. 3 is a sectional view, taken along lines 3-3 of FIG. 2,showing the relationship between the side retainer plates of the presentinvention and the packer pins.

[0025]FIG. 4 is a perspective view of a side retainer plate of thepresent invention.

DESCRIPTION OF THE PRESENTLY PREFERRED EMBODIMENT

[0026] With reference to the drawings, and particularly to FIG. 1, anisometric view of a ram type blowout preventer 10 used in oil and gasdrilling operations is shown. The ram type blowout preventer 10 includesa body or housing 12 with a vertical bore 14 and laterally disposed ramguideways 16. Bonnet assemblies 18 are mounted to the body 12 withsuitable securing means such as studs or bolts 20 and aligned withlaterally disposed guideways 16. Each bonnet assembly 18 includes anactuation means 22, including a piston 24 and connecting rod 26. Whileonly one guideway 16 and actuation means 22 is shown, it is understoodby those of ordinary skill in the art that there is a pair of opposedguideways 16 and actuation means 22. Each connecting rod 26 is connectedto a ram 28 which includes variable bore ram packer 30. Side retainerplates 32 of the present invention are positioned within variable boreram packer 30. Actuation means 22 allows ram 28 and variable bore rampacker 30 to be reciprocated within guideways 16 or “opening and closingthe rams” as it is referred to in the industry.

[0027] Variable bore ram packer 30 is shown in an exploded view in FIG.2 to aid in understanding the relationship between the parts. Variablebore ram packer 30 includes packer member 34 of an elastomeric materialwith suitable rheological characteristics and packer inserts 36 moldedinto one unitary structure with packer inserts 36 arranged around acentral opening 38 to form an insert array 40 that is sized to fitclosely about a tubular member. Packer pins 42 are molded into variablebore ram packer 30 for connecting variable bore ram packer 30 to ram 28.Packer member 34 is molded to form side block seals 44 on its lateraledges. Ram 28 includes top seal 46 on its upper face. Top seal 46 andside block seals 44 combine to seal ram 28 in guideways 16 of ram typeblowout preventer 10 in a manner well known to those of ordinary skillin the art. When rams 28 are closed around a tubular member disposed inbore 14 of ram type blowout preventer 10, packer members 34 seal aroundthe tubular member.

[0028] Side block seals 44 have a curved outer surface 48 to conform tothe shape of guideways 16 to allow reciprocation therein and aid insealing. Side block seals 44 include upper face 50 and lower face 52with side retainer plates 32 molded therein. As best seen in FIG. 4,side retainer plate 32 includes planar portion 54 and depending portionor lip 56. Planar portion 54 includes elongated pin slot 58 forengagement with packer pin 42 in a manner to be explained hereinafter.Depending portion or lip 56 is shaped to approximate the curvature ofcurved outer surface 48 and be molded therein as seen in FIG. 2. Theshape and positioning of depending portion or lip 56 within side blockseal 44 aids in preventing excessive rubber extrusion when side blockseal 44 and variable bore ram packer 30 are in the closed position andsubjected to well bore pressure or test pressure.

[0029] Referring to FIG. 3, the interaction of packer pins 42, wingretainer plates 32 and side block seal 44 is shown. Packer pins 42include horizontal portion 60 and vertical portion 62 in theperpendicular orientation shown. Horizontal portion 60 includes slot 64for engagement with pins 66 molded into top seal 46. Vertical portion 62includes reduced diameter end segments 68 that engage elongated pinslots 58.

[0030] Referring back to FIG. 2, packer inserts 36 include top plate 70,bottom plate 72 and central web 74. Top plate 70 and bottom plate 72 aresubstantially triangular in shape with central web 74 positionedthereon. Central web 74 is integrally formed with top plate 70 andbottom plate 72 by suitable means as casting. Top plate 70 and bottomplate 72 are mirror images of one another and include guide lip 76 andguide shoulder 78 formed on top plate 70 and guide lip 80 and guideshoulder 82 formed on bottom plate 72. Thus, when packer inserts 36 aremolded into packer member 32, guide lips 76 and guide shoulders 78 ofadjacent top plates 70 overlap. Similarly, guide lips 80 and guideshoulders 82 of adjacent bottom plates 72 overlap. Thus, as seen in FIG.2, the assemblies of top plates 70 and bottom plates 72 are arranged toform semi-circular steel arcs similar to that of an “iris” shutter of acamera that acts to prevent extrusion of the elastomeric material ofpacker member 32 in use.

[0031] The construction of my side retainer plate for use in a variablebore ram packer will be readily understood from the foregoingdescription and it will be seen that I have provided a side retainerplate for use in a variable bore ram packer that minimizes rubberextrusion around the sides of the ram packer. Furthermore, while theinvention has been shown and described with respect to certain preferredembodiments, it is obvious that equivalent alterations and modificationswill occur to others skilled in the art upon the reading andunderstanding of the specification. The present invention includes allsuch equivalent alterations and modifications, and is limited only bythe scope of the appended claims.

What is claimed is:
 1. A variable bore packer used in a ram-type blowoutpreventer for oil and gas drilling operations, comprising: a packermember moveable within a ram guideway of a blowout preventer, saidpacker member molded of elastomeric material having a central openingsized to fit closely about a tubular member upon closure of said blowoutpreventer; a plurality of packer inserts molded within said elastomericmaterial into a unitary structure to form an insert array to move andseat against different diameter tubular members to prevent extrusion ofsaid elastomeric material between said packer inserts and the tubularmember; said unitary structure is molded to form a pair of side blockseals integral with said packer member, said side block seals having anupper and lower face; and, a pair of wing retainer plates molded withineach of said upper and lower faces of said side block seals to preventextrusion of said side block seals within said ram guideway of saidblowout preventer.
 2. A variable bore packer used in a ram-type blowoutpreventer for oil and gas drilling operations according to claim 1,wherein: said side block seals substantially conform to said ramguideway of said blowout preventer.
 3. A variable bore packer used in aram-type blowout preventer for oil and gas drilling operations accordingto claim 2, wherein: said wing retainer plates include a planar portionand a depending outer portion, said depending outer portion positionedbelow the surface of said side block seals and adjacent said ramguideway of said blowout preventer.
 4. A variable bore packer used in aram-type blowout preventer for oil and gas drilling operations accordingto claim 3, including: an elongated slot in said planar portion of saidwing retainer plates.
 5. A variable bore packer used in a ram-typeblowout preventer for oil and gas drilling operations according to claim3, further including: a packer pin molded within each of said side blockseals, said packer pin including horizontal and vertical portions, saidvertical portion including reduced diameter end segments that engagesaid elongated slots in said planar portion of said wing retainerplates.
 6. A variable bore packer used in a ram-type blowout preventerfor oil and gas drilling operations according to claim 5, wherein: saidhorizontal portion of said packer pin includes a slot for securing saidpacker member of said variable bore packer to a ram.
 7. A variable borepacker used in a ram-type blowout preventer for oil and gas drillingoperations according to claim 6, wherein: said plurality of packerinserts molded within said elastomeric material surround said centralopening of said packer member.
 8. A variable bore packer used in aram-type blowout preventer for oil and gas drilling operations accordingto claim 7, wherein: said packer inserts include a top plate, a bottomplate and a central web positioned therebetween; and, said top plate,said bottom plate and said central web are integrally formed.
 9. Avariable bore packer used in a ram-type blowout preventer for oil andgas drilling operations according to claim 8, wherein: each of said topand bottom plates includes a guide lip and a guide shoulder; and, saidplurality of packer inserts coact to provide an irising motion to moveand seat against different diameter tubular members.
 10. A ram-typeblowout preventer used in oil and gas drilling operations having avariable bore ram assembly, comprising: a body with a vertical bore; apair of opposing bonnet assemblies laterally disposed in said body; apair of opposing variable bore rams laterally moveable within saidbonnet assemblies; said variable bore rams providing a seal around atubular member having a diameter within a predetermined range, saidtubular member disposed within said vertical bore upon closing of saidvariable bore rams; said pair of variable bore rams each includes a rambody, a top seal and a packer member; a packer member moveable within aram guideway of a blowout preventer, said packer member molded ofelastomeric material having a central opening sized to fit closely abouta tubular member upon closure of said blowout preventer; a plurality ofpacker inserts molded within said elastomeric material into a unitarystructure to form an insert array to move and seat against differentdiameter tubular members to prevent extrusion of said elastomericmaterial between said packer inserts and the tubular member; saidunitary structure is molded to form a pair of side block seals integralwith said packer member, said side block seals having an upper and lowerface; and, a pair of wing retainer plates molded within each of saidupper and lower faces of said side block seals to prevent extrusion ofsaid side block seals within said ram guideway of said blowoutpreventer.
 11. A ram-type blowout preventer used in oil and gas drillingoperations having a variable bore ram assembly according to claim 10,wherein: said side block seals substantially conform to said ramguideway of said blowout preventer.
 12. A ram-type blowout preventerused in oil and gas drilling operations having a variable bore ramassembly according to claim 11, wherein: said wing retainer platesinclude a planar portion and a depending outer portion, said dependingouter portion positioned below the surface of said side block seals andadjacent said ram guideway of said blowout preventer.
 13. A ram-typeblowout preventer used in oil and gas drilling operations having avariable bore ram assembly according to claim 12, including: anelongated slot in said planar portion of said wing retainer plates. 14.A ram-type blowout preventer used in oil and gas drilling operationshaving a variable bore ram assembly according to claim 13, furtherincluding: a packer pin molded within each of said side block seals,said packer pin including horizontal and vertical portions, saidvertical portion including reduced diameter end segments that engagesaid elongated slots in said planar portion of said wing retainerplates.
 15. A ram-type blowout preventer used in oil and gas drillingoperations having a variable bore ram assembly according to claim 14,wherein: said horizontal portion of said packer pin includes a slot forsecuring said packer member of said variable bore packer to a ram.
 16. Aram-type blowout preventer used in oil and gas drilling operationshaving a variable bore ram assembly according to claim 15, wherein: saidplurality of packer inserts molded within said elastomeric materialsurround said central opening of said packer member.
 17. A ram-typeblowout preventer used in oil and gas drilling operations having avariable bore ram assembly according to claim 16, including: said packerinserts include a top plate, a bottom plate and a central web positionedtherebetween; and, said top plate, said bottom plate and said centralweb are integrally formed.
 18. A ram-type blowout preventer used in oiland gas drilling operations having a variable bore ram assemblyaccording to claim 17, including: each of said top and bottom platesincludes a guide lip and a guide shoulder; and, said plurality of packerinserts coact to provide an irising motion to move and seat againstdifferent diameter tubular members.